diff --git a/src/backend/optimizer/plan/planner.c b/src/backend/optimizer/plan/planner.c
index a6ce96e..96def6b 100644
--- a/src/backend/optimizer/plan/planner.c
+++ b/src/backend/optimizer/plan/planner.c
@@ -2402,13 +2402,8 @@ build_grouping_chain(PlannerInfo *root,
 	 * Prepare the grpColIdx for the real Agg node first, because we may need
 	 * it for sorting
 	 */
-	if (list_length(rollup_groupclauses) > 1)
-	{
-		Assert(rollup_lists && llast(rollup_lists));
-
-		top_grpColIdx =
-			remap_groupColIdx(root, llast(rollup_groupclauses));
-	}
+	if (parse->groupingSets)
+		top_grpColIdx = remap_groupColIdx(root, llast(rollup_groupclauses));
 
 	/*
 	 * If we need a Sort operation on the input, generate that.
@@ -2429,11 +2424,14 @@ build_grouping_chain(PlannerInfo *root,
 	while (list_length(rollup_groupclauses) > 1)
 	{
 		List	   *groupClause = linitial(rollup_groupclauses);
-		List	   *gsets = linitial(rollup_lists);
+		List	   *gsets;
 		AttrNumber *new_grpColIdx;
 		Plan	   *sort_plan;
 		Plan	   *agg_plan;
 
+		Assert(rollup_lists && linitial(rollup_lists));
+		gsets = linitial(rollup_lists);
+
 		Assert(groupClause);
 		Assert(gsets);
 
diff --git a/src/test/regress/expected/groupingsets.out b/src/test/regress/expected/groupingsets.out
index 5c47717..4ff5963 100644
--- a/src/test/regress/expected/groupingsets.out
+++ b/src/test/regress/expected/groupingsets.out
@@ -755,4 +755,27 @@ select array(select row(v.a,s1.*) from (select two,four, count(*) from onek grou
  {"(2,0,0,250)","(2,0,2,250)","(2,0,,500)","(2,1,1,250)","(2,1,3,250)","(2,1,,500)","(2,,0,250)","(2,,1,250)","(2,,2,250)","(2,,3,250)","(2,,,1000)"}
 (2 rows)
 
+-- Grouping on text columns
+select sum(ten) from onek group by two, rollup(four::text) order by 1;
+ sum  
+------
+ 1000
+ 1000
+ 1250
+ 1250
+ 2000
+ 2500
+(6 rows)
+
+select sum(ten) from onek group by rollup(four::text), two order by 1;
+ sum  
+------
+ 1000
+ 1000
+ 1250
+ 1250
+ 2000
+ 2500
+(6 rows)
+
 -- end
diff --git a/src/test/regress/sql/groupingsets.sql b/src/test/regress/sql/groupingsets.sql
index e478d34..cc5b89a 100644
--- a/src/test/regress/sql/groupingsets.sql
+++ b/src/test/regress/sql/groupingsets.sql
@@ -205,4 +205,8 @@ group by rollup(ten);
 select * from (values (1),(2)) v(a) left join lateral (select v.a, four, ten, count(*) from onek group by cube(four,ten)) s on true order by v.a,four,ten;
 select array(select row(v.a,s1.*) from (select two,four, count(*) from onek group by cube(two,four) order by two,four) s1) from (values (1),(2)) v(a);
 
+-- Grouping on text columns
+select sum(ten) from onek group by two, rollup(four::text) order by 1;
+select sum(ten) from onek group by rollup(four::text), two order by 1;
+
 -- end